1. Field of the Invention
This invention relates to dispensing systems and more particularly to a variable restrictor for a manually actuated pump for dispensing a liquid from a container. More particularly, this invention relates to a variable restrictor for a manually actuated pump having an actuator movable between an extended position and a retracted position with an adjustable restrictor for varying the output of the manually actuated pump.
2. Background of the Invention
Dispensing systems such as hand operated pumps have been used to dispense a wide variety of products such as household, institutional and personal care products and the like. A hand operated pump comprises a body defining an internal pump cylinder for receiving a reciprocating piston slidably disposed within the internal pump cylinder. The pump is secured to a container for receiving liquid from the container through an induction tube. A pump stem extends from the body in conjunction with a piston having a spring biasing the piston and the stem into an extended position. An actuator having a terminal orifice is secured to the pump stem for enabling a operator to reciprocate the piston within the body. A plurality of one-way valves are disposed within the combination of the piston, stem and body for enabling the liquid to be collected and dispensed through the terminal orifice upon movement of the actuator from the extended position to a retracted position.
In some circumstances, it is desirable to change the volume of liquid discharged from a dispenser when the actuator is moved from the extended position to a retracted position. Various means have been devised in the prior art for changing the volume output of devices unrelated to hand operated pumps.
U.S. Pat. No. 2,530,909 to Riggs relates to a pipette which is adapted for use by milk inspectors during the period of testing for bacteria which may be present in the milk.
U.S. Pat. No. 3,191,807 to Rodrigues, Jr. relates to the dispensing of liquids in equal volumes, and more particularly to the dispensing of equal amounts of liquid in the ultra-micro range.
U.S. Pat. No. 3,343,539 to Moorhouse relates to a syringe comprising a reservoir, a piston and adjusting means for predetermining a quantity of material to be drawn and discharged from the reservoir with each stroke of the piston.
U.S. Pat. No. 3,754,687 to Norton relates to a pipetting dispenser of the piston-cylinder type with adjustable stop means to limit travel of the piston within predetermined limits for insuring the repeated dispensing of like volumes of liquid from said pipette in successive operations of the dispenser for any adjusted position of the stop means.
U.S. Pat. No. 3,759,425 to Lee relates to a syringe gun suitable for dispensing liquid for discharging the contents of a barrel therefrom, an inlet valve enabling the passage of liquid or semi-liquid into the barrel, and a discharge valve enabling the passage of liquid or semi-liquid out of the barrel. At least one of said valves is the combination of a chamber, an inlet orifice to the chamber, a plate within the chamber of substantially greater cross-sectional area than that of the inlet orifice, the plate having an inlet side and an outlet side, a passage for liquid or semi-liquid from the inlet side of the plate to the outlet side of the plate, and an outlet orifice for enabling the passage of liquid or semi-liquid from the chamber. In this valve arrangement the plate seals the inlet orifice under pressure upon the outlet side of the plate and, in the alternative, permits the passage of liquid or semi-liquid through the inlet orifice, by the flexing or moving of the plate away from the inlet orifice and through said passage to the outlet orifice by flexing of the resilient plate or the moving of a floating plate from the inlet orifice, and through said passage to the outlet orifice.
Others in the prior art have incorporated means for locking a hand operated pump in an inoperative position. U.S. Pat. No. 3,827,605 to Knickerbocker relates to a liquid dispensing pump having a pump plunger guided for axial operative movement through a container closure member. A locking collar was mounted for rotary movement to deflect adjacent locking tongues into the path of operative movement of the plunger for immobilize the plunger.
U.S. Pat. No. 3,827,606 to Knickerbocker relates to a liquid dispensing pump having a pump plunger guided for axial operative movement through a container closure cap with a rotary control member mounted on the closure cap. Locking fingers project upwardly from the closure cap having radially deflectable shaft portions which may be deflected into locking relation with the pump plunger to immobilize the pump plunger.
Although the aforementioned prior references have contributed to the dispensing art, there is a need in the art for an improved manually actuated pump for dispensing a liquid from a container which provides a variable output from the pump.
Therefore, it is an object of this invention to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container that is easy to vary the volume output of a hand operated pump.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container wherein the variable output manually operated pump is simple to operate by the operator.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container that does-not appreciably increase material cost of the manually operated pump.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container that is easy to manufacture.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container that does not appreciably increase the overall manufacturing cost of the pump.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container wherein the actuator remains aligned during actuation by an operator.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container wherein the pump may be varied with a minimal adjustment by the operator.
Another object of this invention is to provide a variable restrictor for a manually actuated pump for dispensing a liquid from a container incorporating a variable restrictor that is external to the body to inhibit contamination from product residue and the like.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.